forms.py

   1 from django import forms
   2 from django.contrib.admin.widgets import AdminTextareaWidget
   3 from django.contrib.contenttypes.generic import BaseGenericInlineFormSet
   4 from django.contrib.contenttypes.models import ContentType
   5 from django.core.exceptions import ValidationError, ObjectDoesNotExist
   6 from django.db.models import Q
   7 from django.forms.models import model_to_dict, fields_for_model, ModelFormMetaclass, ModelForm, BaseInlineFormSet
   8 from django.forms.formsets import TOTAL_FORM_COUNT
   9 from django.template import loader, loader_tags, TemplateDoesNotExist, Context, Template as DjangoTemplate
  10 from django.utils.datastructures import SortedDict
  11 from philo.admin.widgets import ModelLookupWidget
  12 from philo.models import Entity, Template, Contentlet, ContentReference, Attribute
  13 from philo.utils import fattr
  14
  15
  16 __all__ = ('EntityForm', )
  17
  18
  19 def proxy_fields_for_entity_model(entity_model, fields=None, exclude=None, widgets=None, formfield_callback=lambda f, **kwargs: f.formfield(**kwargs)):
  20         field_list = []
  21         ignored = []
  22         opts = entity_model._entity_meta
  23         for f in opts.proxy_fields:
  24                 if not f.editable:
  25                         continue
  26                 if fields and not f.name in fields:
  27                         continue
  28                 if exclude and f.name in exclude:
  29                         continue
  30                 if widgets and f.name in widgets:
  31                         kwargs = {'widget': widgets[f.name]}
  32                 else:
  33                         kwargs = {}
  34                 formfield = formfield_callback(f, **kwargs)
  35                 if formfield:
  36                         field_list.append((f.name, formfield))
  37                 else:
  38                         ignored.append(f.name)
  39         field_dict = SortedDict(field_list)
  40         if fields:
  41                 field_dict = SortedDict(
  42                         [(f, field_dict.get(f)) for f in fields
  43                                 if ((not exclude) or (exclude and f not in exclude)) and (f not in ignored) and (f in field_dict)]
  44                 )
  45         return field_dict
  46
  47
  48 # BEGIN HACK - This will not be required after http://code.djangoproject.com/ticket/14082 has been resolved
  49
  50 class EntityFormBase(ModelForm):
  51         pass
  52
  53 _old_metaclass_new = ModelFormMetaclass.__new__
  54
  55 def _new_metaclass_new(cls, name, bases, attrs):
  56         new_class = _old_metaclass_new(cls, name, bases, attrs)
  57         if issubclass(new_class, EntityFormBase) and new_class._meta.model:
  58                 new_class.base_fields.update(proxy_fields_for_entity_model(new_class._meta.model, new_class._meta.fields, new_class._meta.exclude, new_class._meta.widgets)) # don't pass in formfield_callback
  59         return new_class
  60
  61 ModelFormMetaclass.__new__ = staticmethod(_new_metaclass_new)
  62
  63 # END HACK
  64
  65
  66 class EntityForm(EntityFormBase): # Would inherit from ModelForm directly if it weren't for the above HACK
  67         def __init__(self, *args, **kwargs):
  68                 initial = kwargs.pop('initial', None)
  69                 instance = kwargs.get('instance', None)
  70                 if instance is not None:
  71                         new_initial = {}
  72                         for f in instance._entity_meta.proxy_fields:
  73                                 if self._meta.fields and not f.name in self._meta.fields:
  74                                         continue
  75                                 if self._meta.exclude and f.name in self._meta.exclude:
  76                                         continue
  77                                 new_initial[f.name] = f.value_from_object(instance)
  78                 else:
  79                         new_initial = {}
  80                 if initial is not None:
  81                         new_initial.update(initial)
  82                 kwargs['initial'] = new_initial
  83                 super(EntityForm, self).__init__(*args, **kwargs)
  84
  85         @fattr(alters_data=True)
  86         def save(self, commit=True):
  87                 cleaned_data = self.cleaned_data
  88                 instance = super(EntityForm, self).save(commit=False)
  89
  90                 for f in instance._entity_meta.proxy_fields:
  91                         if not f.editable or not f.name in cleaned_data:
  92                                 continue
  93                         if self._meta.fields and f.name not in self._meta.fields:
  94                                 continue
  95                         if self._meta.exclude and f.name in self._meta.exclude:
  96                                 continue
  97                         setattr(instance, f.attname, cleaned_data[f.name])
  98
  99                 if commit:
 100                         instance.save()
 101                         self.save_m2m()
 102
 103                 return instance
 104
 105
 106 class AttributeForm(ModelForm):
 107         def __init__(self, *args, **kwargs):
 108                 super(AttributeForm, self).__init__(*args, **kwargs)
 109
 110                 # This is necessary because model forms store changes to self.instance in their clean method.
 111                 # Mutter mutter.
 112                 self._cached_value_ct = self.instance.value_content_type
 113                 self._cached_value = self.instance.value
 114
 115                 if self.instance.value is not None:
 116                         value_field = self.instance.value.value_formfield()
 117                         if value_field:
 118                                 self.fields['value'] = value_field
 119                         if hasattr(self.instance.value, 'content_type'):
 120                                 self.fields['content_type'] = self.instance.value._meta.get_field('content_type').formfield(initial=getattr(self.instance.value.content_type, 'pk', None))
 121
 122         def save(self, *args, **kwargs):
 123                 # At this point, the cleaned_data has already been stored on self.instance.
 124                 if self.instance.value_content_type != self._cached_value_ct:
 125                         if self.instance.value is not None:
 126                                 self._cached_value.delete()
 127                                 if 'value' in self.cleaned_data:
 128                                         del(self.cleaned_data['value'])
 129
 130                         if self.instance.value_content_type is not None:
 131                                 # Make a blank value of the new type! Run special code for content_type attributes.
 132                                 if hasattr(self.instance.value_content_type.model_class(), 'content_type'):
 133                                         if self._cached_value and hasattr(self._cached_value, 'content_type'):
 134                                                 new_ct = self._cached_value.content_type
 135                                         else:
 136                                                 new_ct = None
 137                                         new_value = self.instance.value_content_type.model_class().objects.create(content_type=new_ct)
 138                                 else:
 139                                         new_value = self.instance.value_content_type.model_class().objects.create()
 140
 141                                 new_value.apply_data(self.cleaned_data)
 142                                 new_value.save()
 143                                 self.instance.value = new_value
 144                 else:
 145                         # The value type is the same, but one of the fields has changed.
 146                         # Check to see if the changed value was the content type. We have to check the
 147                         # cleaned_data because self.instance.value.content_type was overridden.
 148                         if hasattr(self.instance.value, 'content_type') and 'content_type' in self.cleaned_data and 'value' in self.cleaned_data and (not hasattr(self._cached_value, 'content_type') or self._cached_value.content_type != self.cleaned_data['content_type']):
 149                                 self.cleaned_data['value'] = None
 150
 151                         self.instance.value.apply_data(self.cleaned_data)
 152                         self.instance.value.save()
 153
 154                 super(AttributeForm, self).save(*args, **kwargs)
 155                 return self.instance
 156
 157         class Meta:
 158                 model = Attribute
 159
 160
 161 class AttributeInlineFormSet(BaseGenericInlineFormSet):
 162         "Necessary to force the GenericInlineFormset to use the form's save method for new objects."
 163         def save_new(self, form, commit):
 164                 setattr(form.instance, self.ct_field.get_attname(), ContentType.objects.get_for_model(self.instance).pk)
 165                 setattr(form.instance, self.ct_fk_field.get_attname(), self.instance.pk)
 166                 return form.save()
 167
 168
 169 class ContainerForm(ModelForm):
 170         def __init__(self, *args, **kwargs):
 171                 super(ContainerForm, self).__init__(*args, **kwargs)
 172                 self.verbose_name = self.instance.name.replace('_', ' ')
 173
 174
 175 class ContentletForm(ContainerForm):
 176         content = forms.CharField(required=False, widget=AdminTextareaWidget, label='Content')
 177
 178         def should_delete(self):
 179                 return not bool(self.cleaned_data['content'])
 180
 181         class Meta:
 182                 model = Contentlet
 183                 fields = ['name', 'content']
 184
 185
 186 class ContentReferenceForm(ContainerForm):
 187         def __init__(self, *args, **kwargs):
 188                 super(ContentReferenceForm, self).__init__(*args, **kwargs)
 189                 try:
 190                         self.fields['content_id'].widget = ModelLookupWidget(self.instance.content_type)
 191                 except ObjectDoesNotExist:
 192                         # This will happen when an empty form (which we will never use) gets instantiated.
 193                         pass
 194
 195         def should_delete(self):
 196                 return (self.cleaned_data['content_id'] is None)
 197
 198         class Meta:
 199                 model = ContentReference
 200                 fields = ['name', 'content_id']
 201
 202
 203 class ContainerInlineFormSet(BaseInlineFormSet):
 204         def __init__(self, containers, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 205                 # Unfortunately, I need to add some things to BaseInline between its __init__ and its
 206                 # super call, so a lot of this is repetition.
 207
 208                 # Start cribbed from BaseInline
 209                 from django.db.models.fields.related import RelatedObject
 210                 self.save_as_new = save_as_new
 211                 # is there a better way to get the object descriptor?
 212                 self.rel_name = RelatedObject(self.fk.rel.to, self.model, self.fk).get_accessor_name()
 213                 if self.fk.rel.field_name == self.fk.rel.to._meta.pk.name:
 214                         backlink_value = self.instance
 215                 else:
 216                         backlink_value = getattr(self.instance, self.fk.rel.field_name)
 217                 if queryset is None:
 218                         queryset = self.model._default_manager
 219                 qs = queryset.filter(**{self.fk.name: backlink_value})
 220                 # End cribbed from BaseInline
 221
 222                 self.container_instances, qs = self.get_container_instances(containers, qs)
 223                 self.extra_containers = containers
 224                 self.extra = len(self.extra_containers)
 225                 super(BaseInlineFormSet, self).__init__(data, files, prefix=prefix, queryset=qs)
 226
 227         def get_container_instances(self, containers, qs):
 228                 raise NotImplementedError
 229
 230         def total_form_count(self):
 231                 if self.data or self.files:
 232                         return self.management_form.cleaned_data[TOTAL_FORM_COUNT]
 233                 else:
 234                         return self.initial_form_count() + self.extra
 235
 236         def save_existing_objects(self, commit=True):
 237                 self.changed_objects = []
 238                 self.deleted_objects = []
 239                 if not self.get_queryset():
 240                         return []
 241
 242                 saved_instances = []
 243                 for form in self.initial_forms:
 244                         pk_name = self._pk_field.name
 245                         raw_pk_value = form._raw_value(pk_name)
 246
 247                         # clean() for different types of PK fields can sometimes return
 248                         # the model instance, and sometimes the PK. Handle either.
 249                         pk_value = form.fields[pk_name].clean(raw_pk_value)
 250                         pk_value = getattr(pk_value, 'pk', pk_value)
 251
 252                         obj = self._existing_object(pk_value)
 253                         if form.should_delete():
 254                                 self.deleted_objects.append(obj)
 255                                 obj.delete()
 256                                 continue
 257                         if form.has_changed():
 258                                 self.changed_objects.append((obj, form.changed_data))
 259                                 saved_instances.append(self.save_existing(form, obj, commit=commit))
 260                                 if not commit:
 261                                         self.saved_forms.append(form)
 262                 return saved_instances
 263
 264         def save_new_objects(self, commit=True):
 265                 self.new_objects = []
 266                 for form in self.extra_forms:
 267                         if not form.has_changed():
 268                                 continue
 269                         # If someone has marked an add form for deletion, don't save the
 270                         # object.
 271                         if form.should_delete():
 272                                 continue
 273                         self.new_objects.append(self.save_new(form, commit=commit))
 274                         if not commit:
 275                                 self.saved_forms.append(form)
 276                 return self.new_objects
 277
 278
 279 class ContentletInlineFormSet(ContainerInlineFormSet):
 280         def __init__(self, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 281                 if instance is None:
 282                         self.instance = self.fk.rel.to()
 283                 else:
 284                         self.instance = instance
 285
 286                 try:
 287                         containers = list(self.instance.containers[0])
 288                 except ObjectDoesNotExist:
 289                         containers = []
 290
 291                 super(ContentletInlineFormSet, self).__init__(containers, data, files, instance, save_as_new, prefix, queryset)
 292
 293         def get_container_instances(self, containers, qs):
 294                 qs = qs.filter(name__in=containers)
 295                 container_instances = []
 296                 for container in qs:
 297                         container_instances.append(container)
 298                         containers.remove(container.name)
 299                 return container_instances, qs
 300
 301         def _construct_form(self, i, **kwargs):
 302                 if i >= self.initial_form_count(): # and not kwargs.get('instance'):
 303                         kwargs['instance'] = self.model(name=self.extra_containers[i - self.initial_form_count() - 1])
 304
 305                 return super(ContentletInlineFormSet, self)._construct_form(i, **kwargs)
 306
 307
 308 class ContentReferenceInlineFormSet(ContainerInlineFormSet):
 309         def __init__(self, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 310                 if instance is None:
 311                         self.instance = self.fk.rel.to()
 312                 else:
 313                         self.instance = instance
 314
 315                 try:
 316                         containers = list(self.instance.containers[1])
 317                 except ObjectDoesNotExist:
 318                         containers = []
 319
 320                 super(ContentReferenceInlineFormSet, self).__init__(containers, data, files, instance, save_as_new, prefix, queryset)
 321
 322         def get_container_instances(self, containers, qs):
 323                 filter = Q()
 324
 325                 for name, ct in containers:
 326                         filter |= Q(name=name, content_type=ct)
 327
 328                 qs = qs.filter(filter)
 329                 container_instances = []
 330                 for container in qs:
 331                         container_instances.append(container)
 332                         containers.remove((container.name, container.content_type))
 333                 return container_instances, qs
 334
 335         def _construct_form(self, i, **kwargs):
 336                 if i >= self.initial_form_count(): # and not kwargs.get('instance'):
 337                         name, content_type = self.extra_containers[i - self.initial_form_count() - 1]
 338                         kwargs['instance'] = self.model(name=name, content_type=content_type)
 339
 340                 return super(ContentReferenceInlineFormSet, self)._construct_form(i, **kwargs)